I had an active connection in MySQL Workbench to my Ubuntu 14.04 over ssh tunnel for last two years without any problem. But after Ubuntu upgrade to new 16.04 I keep receive following error:

13:41:56 [INF][     SSH tunnel]: Starting tunnel

13:41:56 [INF][     SSH tunnel]: Existing SSH tunnel not found, opening new one

13:42:03 [INF][     SSH tunnel]: Opening SSH tunnel to xxx.xxx.xxx.xxx:22

13:42:03 [INF][     SSH tunnel]: TunnelManager.wait_connection authentication error: Authentication error, unhandled exception caught in tunnel manager, please refer to logs for details

13:42:03 [ERR][     SSH tunnel]: Authentication error opening SSH tunnel: Authentication error, unhandled exception caught in tunnel manager, please refer to logs for details

Notes which may be useful:

1. I am able to connect over ssh tunnel by HeidiSQL.


2. I fail to establish connection by Navicat and keep getting
   SSH:expected key exchange group packet from server.

I read a lot to fix this issue some of suggestion are here:

• generate new ssh key on server,


• add KexAlgorithms to end of sshd_config,


• upgrade paramiko package of workbench Python.

I appreciate for any help you will provide.